State environmental officials on Friday sought to quell fears about millions of gallons of potentially polluted water that gushed into Tampa Bay late last month after a leak was discovered at the abandoned Piney Point phosphate plant.
According to the most recent data, there are no quality concerns for metals in Bishop Harbor, an important marine system about a mile from the plant, which sits across from Port Manatee near the Hillsborough-Manatee county line.
"The water quality data looks good," said John Coates, deputy director for the Department of Environmental Protection's division of water resources management.
In May, contractors working on a dredge project at the port noticed a tear in the reservoir atop the phosphogypsum stack at the plant.
State officials, fearing the gypsum stacks would collapse and pour radioactive material into the bay, issued an emergency order May 29 to discharge the reservoir water into ditches that flow into Bishop Harbor.
Early results indicated the water, mainly seawater, had high levels of cadmium, a heavy metal found naturally in rocks and used in metal plating and coating. Too much of it in drinking water can cause health problems.
But the latest data, gathered last week, show that the level of cadmium in Bishop Harbor is less than one-tenth of the allowable marine water quality standard, state officials said Friday.
"We think that's very good news for the monitoring we have at this point," Coates said, adding that he doesn't believe there will be any problem with fish kills or algae blooms in the harbor.
The leak in the reservoir is still under investigation.
Crews were putting the finishing touches on a cofferdam on Friday to isolate the trouble spot.
"That cofferdam will separate where the leak is from the rest of the reservoir," Coates said.
The discharge went into a freshwater drainage ditch along north side of Buckeye Road. Cadmium levels remain high there, Coates said, but he emphasized that there are different water quality standards for freshwater and the Bishop Harbor marine system.
More testing at both sites was conducted this week, with results expected sometime in the next several days.
"I am going to remain optimistic, but cautious," Coates said. "We're going to continue to monitor this."
Kameel Stanley can be reached at firstname.lastname@example.org or (727) 893-8643.